Уменьшите массив до определенной структуры, используя javascript


У меня есть массив объектов 

[
    {"id":"brand","label":"Brand","value":"value1"},    
    {"id":"waterproof","label":"Waterproof","value":"value1"},
    {"id":"diameter","label":"Diameter","value":""},
    {"id":"brand","label":"Brand","value":"value2"},
    {"id":"waterproof","label":"Waterproof","value":"value2"},
    {"id":"diameter","label":"Diameter","value":""}
]

Мне нужно перестроить его в следующую структуру, 

[
    ["Brand", "value1", "value2"], 
    ["Waterproof", "value1","value2"], 
    ["Diameter","",""]
]

Любые идеи о том, как я могу это сделать, используя метод уменьшения.

Лучший

javascriptarraysobject

Всего 6 ответов

Попробуйте выполнить команду Array.reduce и Object.values 

 let arr = [{"id":"brand","label":"Brand","value":"value1"},{"id":"waterproof","label":"Waterproof","value":"value1"},{"id":"diameter","label":"Diameter","value":""},{"id":"brand","label":"Brand","value":"value2"},{"id":"waterproof","label":"Waterproof","value":"value2"},{"id":"diameter","label":"Diameter","value":""}]; let result = Object.values(arr.reduce((a,c) => { if(a[c.id]) a[c.id].push(c.value); else a[c.id] = [c.label, c.value]; return a; }, {})); console.log(result);

Юст возьмите Map и соберите все значения. 

 var json = '[{"id":"brand","label":"Brand","value":"value1"},{"id":"waterproof","label":"Waterproof","value":"value1"},{"id":"diameter","label":"Diameter","value":""},{"id":"brand","label":"Brand","value":"value2"},{"id":"waterproof","label":"Waterproof","value":"value2"},{"id":"diameter","label":"Diameter","value":""}]', result = Array.from(JSON .parse(json) .reduce((m, { id, label, value }) => m.set(id, (m.get(id) || [label]).concat(value)), new Map) .values() ); console.log(result); 
 .as-console-wrapper { max-height: 100% !important; top: 0; }

Не лучший код, но я думаю, что это может быть полезно для вас: 

let data = [
        {"id":"brand","label":"Brand","value":"value1"},    
        {"id":"waterproof","label":"Waterproof","value":"value1"},
        {"id":"diameter","label":"Diameter","value":""},
        {"id":"brand","label":"Brand","value":"value2"},
        {"id":"waterproof","label":"Waterproof","value":"value2"},
        {"id":"diameter","label":"Diameter","value":""}
    ]

    let reducedData = {}
    data.forEach((row)=>{
        reducedData[row.id] ? reducedData[row.id].push(row.value) : reducedData[row.id] = [row.label, row.value]    
    })
    let newData = Object.keys(reducedData).map((id)=>{return [...reducedData[id]]})

Вы также можете использовать простую комбинацию Array.prototype.reduce и Object.keys : 

 const data = [{"id":"brand","label":"Brand","value":"value1"},{"id":"waterproof","label":"Waterproof","value":"value1"},{"id":"diameter","label":"Diameter","value":""},{"id":"brand","label":"Brand","value":"value2"},{"id":"waterproof","label":"Waterproof","value":"value2"},{"id":"diameter","label":"Diameter","value":""}]; const grouped = data.reduce((o, { label, value }) => ({...o, [label]: [...(o[label] || []), value]}), {}); const result = Object.keys(grouped).map(label => [label, ...grouped[label]]); console.log(result);

Здесь я использую Set для создания уникального списка id , а затем я map для создания настраиваемого массива на основе этих id . Это делается с помощью find для получения метки и фильтра, чтобы получить все элементы, связанные с id . Я снова сопоставляю фильтр, чтобы просто вернуть value объекта. 

 let items = [ {"id":"brand","label":"Brand","value":"value1"}, {"id":"waterproof","label":"Waterproof","value":"value1"}, {"id":"diameter","label":"Diameter","value":""}, {"id":"brand","label":"Brand","value":"value2"}, {"id":"waterproof","label":"Waterproof","value":"value2"}, {"id":"diameter","label":"Diameter","value":""} ] let result = [...new Set(items.map(i => i.id))] .map(id => { return [ items.find(i => i.id == id).label, ...items.filter(i => i.id == id).map(i => i.value) ] }) console.log(result)

Если массив JSON очень длинный из некоторого API 

var data = [
    {"id":"brand","label":"Brand","value":"value1"},    
    {"id":"waterproof","label":"Waterproof","value":"value1"},
    ...... //some JSON array form some API
];
var json = JSON.stringify(data);

result = Array.from(JSON
    .parse(json)
    .reduce((m, { id, label, value }) => m.set(id, (m.get(id) || [label]).concat(value)), new Map)
    .values()
);
console.log(result);